Steam now hosts more than 40 million accounts and 1,800 games, and its 2011 year-over-year sales increased 100 percent for the seventh year in a row, Valve announced today with a ridiculously smug grin on its face (we assume). During the Holiday Sale, Steam clocked more than 5 million simultaneous users -- in perspective, that's easily more people than the entire population of Norway, all on Steam at the same time.

Steam served over 780 petabytes of data to gamers in 2011, more than doubling the amount delivered in 2010, Valve reported. More than 19 million items were traded in-game, Valve president Gabe Newell said, and he promised that more free-to-play titles will be launched in 2012 to supplement the 18 Steam already hosts.

Newell hasn't forgotten about Big Picture Mode, Valve's attempt to infiltrate living rooms with a top-boxy device that will offer Steam via controller navigation on "more screens throughout the house." Newell said Valve is "preparing for the launch" of Big Picture Mode, so we're guessing we can expect to see something concrete by 2015.